Genetic Features of Triticale–Wheat Hybrids with Vaviloid-Type Spike Branching

Abstract

Vaviloid spike branching, also called sham ramification, is a typical trait of Triticum vavilovii Jakubz. and is characterized by a lengthening of the spikelet axis. In this article, we present the results of a study of three triticale–wheat hybrid lines with differences in terms of the manifestation of the vaviloid spike branching. Lines were obtained by crossing triticale with hexaploid wheat, T. aestivum var. velutinum. The parental triticale is a hybrid of synthetic wheat (T. durum × Ae. tauschii var. meyrei) with rye, S. cereale ssp. segetale. Line 857 has a karyotype corresponding to hexaploid wheat and has a spike morphology closest to normal, whereas Lines 808/1 and 844/4 are characterized by the greatest manifestation of vaviloid spike branching. In Lines 808/1 and 844/4, we found the substitution 2RL(2DL). The karyotypes of the latter lines differ in that a pair of telocentric chromosomes 2DS is detected in Line 808/1, and these telocentrics are fused into one unpaired chromosome in Line 844/4. Using molecular genetic analysis, we found a deletion of the wheat domestication gene Q located on 5AL in the three studied hybrid lines. The deletion is local since an analysis of the adjacent gene B1 showed the presence of this gene. We assume that the manifestation of vaviloid spike branching in two lines (808/1 and 844/4) is associated with a disturbance in the joint action of genes Q and AP2L2-2D, which is another important gene that determines spike morphology and is located on 2DL.

Identification of molecular markers and candidate regions associated with grain number per spike in Pubing3228 using SLAF-BSA

“…The AP2 transcription factor family, including the Q gene ( AP2L5 ) and its associated paralog AP2L2 , is regulated by miRNA172 and demonstrates critical and redundant functions in specifying axillary floral meristems ( Debernardi et al., 2020 ). The proper balance of AP2-like gene expression, located on chromosomes 5AL (Q), 2AL ( AP2L2-2A ), 2BL ( AP2L2-2B ), and 2DL ( AP2L2 ), is essential for spikelet and floret development ( Adonina et al., 2021 ). Structural reorganization of a chromosome during hybridization can disrupt this balance, thereby offering an opportunity to modify spikelet structure and potentially improve grain yield by manipulating this regulatory module.The WFZP gene, a member of the AP2/ERF transcription factor family, has been experimentally demonstrated to regulate spikelet development and exhibits conserved functionality between wheat and Brachypodium.…”

Molecular cytological analysis of alien introgressions in common wheat lines created by crossing of <i>Triticum aestivum</i> with <i>T. dicoccoides</i> and <i>T. dicoccum</i>

“…Therefore, for a more accurate description of chromosomal rearrangements, it is optimal to use both molecular and cytological methods. This has been demonstrated in different studies where hybrid forms from crossing different types of wheat, barley and triticale were investigated (Silkova et al, 2006;Mattera et al, 2015;Adonina et al, 2022).…”